1. Field of the Invention
The present invention relates to a radiographic apparatus to conduct an imaging of a transmissive image of a subject by using radiation, and to conduct especially a slot radiography to obtain plural rectangular images, and to generate a single image by connecting the obtained images in a width side direction.
2. Description of the Related Art
Referring now to FIG. 11, a conventional radiographic apparatus to take an image of a subject M by radiation is equipped in a medical facility. Such radiographic apparatus 51 comprises a table 52 on which the subject is loaded, a radiation source 53 to irradiate a radiation, and a radiation detector 54. An image in which a transmissive image of the subject M appears based on the signal output from the radiation detector 54 is obtained.
Some of such radiographic apparatus have a constitution which eliminates an effect of scattered radiation to provide a clear image. A manner to take an image by using such radiographic apparatus is illustrated in FIG. 11. The radiation source 53 and the radiation detector 54 move in a length direction of the table 52 while keeping each other's positional relationship. Plural images are taken during this movement. One composite image can be generated by connecting these plural images.
On shooting, a broadening of radiation irradiated from the radiation source 53 is restricted in the length direction of the table. (Referring to FIG. 11) Accordingly, each image taken is a long thin strip image in a width direction of table 52. The region N (in FIG. 11) indicates a part of the incident radiation beam B in the radiation detector 54. This region N is a radiography shooting angle of the radiation detector 54 when a strip image is obtained.
On the other hand, when the radiation passes through a subject M, a part of radiation scatters in the body of the subject M and becomes a scattered radiation S. The scattered radiation S is a cause that leads to an unclear image. Accordingly, it is preferable that the scattered radiation S is eliminated during conducting radiography when an image is taken.
According to a conventional constitution, a turbulence production in an image due to a scattered radiation S is suppressed by repeatedly taking strip images T. Specifically, the scattered radiation occurs in the body of the subject M changes the direction of travel due to scattering. Accordingly, the scattered radiation S directs towards the radiation detector 54 while it is out of the direction of travel of X-ray beam B. Accordingly, the scattered radiation S is not incident in the region N that is a shooting angle when a strip image T is taken. Accordingly, as the scattered radiation S which is a cause to produce turbulence is not an incident radiation, the obtained strip image T is a clear image without an effect of the scattered radiation S.
Then, referring to FIG. 12, a conventional composite image incorporating the whole body image of the subject M can be generated by arraying sequentially obtained strip images T in the length direction of table 52 over time and in order of shooting time. Since this composite image has been generated from images taken over time with excluding a scattered radiation S, it is clear but with the detriment of time. If the body moves in the time the images is not clear.
A radiographic apparatus comprising a means to cut a shooting time by minimizing movement of radiation detector 54 has been provided nowadays. The shorter movement of the radiation detector 54 becomes shorter, within the shorter time frame, the strip images T can be taken continuously. Accordingly, the shooting can be completed without letting the body of the subject M move and thus no disarray of images at the connection point occurs when the strip images T are connected. Accordingly, a composite image having an excellent visual recognition can be generated by such radiographic apparatus. (Patent Document 1 WO 2010/050032), however the shooting time cannot be further decreased.